Question

我正在开发一个Web应用程序并在Tomcat 7.0上部署它。我的应用程序使用MySQL数据库。我已经在app和database之间配置了连接，并希望添加Hibernate 5.2.5支持。我可以通过Hibernate控制台与数据库进行通信，使用下面的配置，在非网络应用程序中使用时可以正常工作。问题出在我将其部署在服务器上时。我收到警告

no persistent classes found for query class: from entities.UserH

然后由它引起500服务器错误。

我的实体类：

@Entity @Table(name = "users", uniqueConstraints = {@UniqueConstraint(columnNames = {"id"})}) public class UserH { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Column(name = "id", nullable = false, unique = true, length = 11) private int id; @Column(name = "login", nullable = false, length = 45) private String login; @Column(name = "name", nullable = false, length = 45) private String name; @Column(name = "surname", nullable = false, length = 45) private String surname; /* getters and setters*/ }

我的hibernate-annotation.cfg.xml：

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory>  <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/web-database</property> <property name="hibernate.connection.username">username</property> <property name="hibernate.connection.password">password</property>  <property name="hibernate.current_session_context_class">thread</property>  <mapping class="entities.UserH"/> </session-factory> </hibernate-configuration>

应该获得用户的方法：

public List<UserH> getAllUsers() { try (Session session = HibernateUtils.getSessionAnnotationFactory().getCurrentSession()) { session.beginTransaction(); Query<UserH> usersQuery = session.createQuery("from entities.UserH", UserH.class); List<UserH> usersList = usersQuery.getResultList(); session.getTransaction().commit(); return usersList; } }

正如我所提到的 - 它适用于普通的应用程序，但不适用于Tomcat。我将所有可用元素添加到网络工件中，但它没有帮助。我甚至试图用persistance.xml添加JPA支持，但仍然没有运气。

还有什么问题？

编辑：我的HibernateUtils类：

public class HibernateUtils { private static SessionFactory sessionAnnotationFactory; private static SessionFactory buildSessionAnnotationFactory() { try { // Create the SessionFactory from hibernate.cfg.xml Configuration configuration = new Configuration(); configuration.configure("hibernate-annotation.cfg.xml"); System.out.println("Hibernate Annotation Configuration loaded"); ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build(); System.out.println("Hibernate Annotation serviceRegistry created"); SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry); return sessionFactory; } catch (Throwable ex) { System.err.println("Initial SessionFactory creation failed." + ex); throw new ExceptionInInitializerError(ex); } } public static SessionFactory getSessionAnnotationFactory() { if (sessionAnnotationFactory == null) sessionAnnotationFactory = buildSessionAnnotationFactory(); return sessionAnnotationFactory; } }

Answer 1

您应该只更改查询以仅引用类名：

session.createQuery( "FROM UserH", UserH.class )

当您将实体定义为内部类时，包唯一重要的时间。

对于这些情况，您需要使用完整的班级名称com.c.SomeOutterClass$MyEntity。另一种方法是更改@Entity注释，使其包含name属性，以便明确命名实体类：

public class SomeOutterClass {
  @Entity(name = "MyEntity")
  public static class MyEntity {

  }
}

Answer 2

也许这不是我的问题的正确答案，但这实际上对我有用。我用JPA配置+ hibernate替换了hibernate。

所以不使用hibernate-annotation.cfg.xml + Session而是使用persistance.xml + EntityManager：

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">

    <persistence-unit name="NewPersistenceUnit" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
        <class>entities.UserH</class>

        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/web-database"/>
            <property name="javax.persistence.jdbc.user" value="Admin"/>
            <property name="javax.persistence.jdbc.password" value="password2@"/>
            <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
            <property name="hibernate.hbm2ddl.auto" value="update"/>
        </properties>
    </persistence-unit>

</persistence>

getEntityManager：

public static EntityManager getEntityManager() {
    EntityManager entityManager = Persistence
            .createEntityManagerFactory("NewPersistenceUnit")
            .createEntityManager();

    return entityManager;
}

getAllUsers：

public List<UserH> getAllUsers() {

    EntityManager entityManager = HibernateUtils.getEntityManager();
    EntityTransaction transaction = entityManager.getTransaction();
    transaction.begin();
    TypedQuery<UserH> usersQuery = entityManager.createQuery("from UserH ", UserH.class);
    List<UserH> usersList = usersQuery.getResultList();
    transaction.commit();
    entityManager.close();

    return usersList;
}

然而，我仍然不明白为什么这种配置有效，而单独的hibernate没有。任何意见/建议将不胜感激。

Tomcat + hibernate =没有为查询类找到持久化类

2 个答案: